Promoting his new book, 'Katrina's Secrets,' on Monday's NBC Today, former New Orleans Mayor Ray Nagin stood by his assertion that racism played a role in the Bush administration's response to the storm: "I'm not telling you that President Bush was a racist or what have you. But I think race and class and politics played in just about every aspect of this disaster."

Co-host Matt Lauer claimed that Nagin was "very honest and open" in the book, at least in his ability to "blame President Bush, FEMA Director Michael Brown and others for slow federal response." After quoting Nagin's suggestion in the book that race was a factor, Lauer referred to the accusation as a "Kanye West moment" and wondered: "What proof do you have that it contributed to the slow response?"

Nagin only offered anecdotal evidence of racial bias: "Well, I look at our response – or the response that happened during Katrina. Then I look at subsequent events, like there was some fires in California, and it was a much different response, a much better response." Lauer did not press any further on the issue.

Later in the interview, Nagin dismissed President Bush's Constitutional concerns in sending National Guard troops into New Orleans without approval from the state of Louisiana: "The Republican president, Democratic governor, arguing over the Posse Comitatus Act that was passed way back in who knows when." Lauer actually defended the caution: "And it's funny because President Bush looked at it from the other way, he worried that a Republican president coming into a state with a Democratic governor and a largely African-American population and declaring martial law basically would be viewed very badly."

Lauer went on to sympathize with Nagin's frustration during the disaster: "In a radio interview you did, I think it was three days after the storm hit, you started to talk about the response....You had reached a tipping point. What was it that put you over the edge?"

Not until the end of the segment did Lauer wonder about Nagin's poor response to the crisis: "...you had your critics....I know you admit in the book that you made mistakes....What was the biggest mistake you made?" Nagin replied: "...the thing that I worry about and I think about the most is could I have called a mandatory evacuation much earlier." Lauer followed up: "You think you could have changed the scope of the suffering?" Nagin softened his self-criticism: "I'm not sure. It was overnight, so most people were preparing to leave that next morning anyway. But it was a window that I think about a lot."

Lauer didn't challenge Nagin any further, but gave the mayor a warm send-off: "Former New Orleans Mayor Ray Nagin. Ray, it's always good to see you. Thank you very much."

Here is a full transcript of the June 20 segment:

8:36AM ET

MATT LAUER: Hurricane Katrina slammed into New Orleans on August 29th, 2005 and forever changed the city and this country. More than 1,000 people died. 80% of that city was flooded when the levees were breached. Mayor Ray Nagin was thrust into the national spotlight as he struggled to handle the disaster. Now a year after leaving office he's written a new book, it's called 'Katrina's Secrets, Storms After the Storm.' Ray Nagin, good to see you again. Welcome.

RAY NAGIN: It's good to see you again, Matt.

LAUER: It's a pleasure. So I was thinking, this is – Katrina, probably the most written about, talked about, argued about, analyzed storm in American history. So what are the secrets we don't know?

NAGIN: Well, Matt, you know, after I got out of office, I had a chance to go back and look at this story. And it's amazingly complex. So I tried to bring my experiences, the front row journey that I had, I interacted with just about every level of government. So I try and bring that perspective.

LAUER: You are very honest and open in this. You do not spare criticism. You blame President Bush, FEMA Director Michael Brown and others for slow federal response. In the book you write this, and I'm quoting, quote, 'The million dollar question is why didn't they take effective action immediately? Was it partisan politics? Were there racial considerations? My humble opinion is that it was all of the above.' Now, this is that Kanye West moment here, Ray. I mean, you know, you remember President Bush bristled-

NAGIN: I remember that.

LAUER: -in the interview he did with me and in his book that there was any consideration of race in this. What proof do you have that it contributed to the slow response?

NAGIN: Well, I look at our response – or the response that happened during Katrina. Then I look at subsequent events, like there was some fires in California, and it was a much different response, a much better response. Now, I'm not telling you that President Bush was a racist or what have you. But I think race and class and politics played in just about every aspect of this disaster.

LAUER: On the political front, it's no secret, doesn't have to be a Katrina's secret, you did not have a very good working relationship with the governor of Louisiana at that time, Kathleen Blanco. As a matter of fact, when she ran for office you crossed party lines and you supported her opponent Bobby Jindal. And when you called to break the news to her, she said, according to you, quote, 'There will be hell to pay.' Do you think that that actually contributed enough friction to where she was uncooperative with helping you and the City of New Orleans?

NAGIN: I don't know about that, but I think there was some residuals. Our relationship was not the best. But there were some things going on above me that I think contributed to her hesitancy more than anything. The Republican president, Democratic governor, arguing over the Posse Comitatus Act that was passed way back in who knows when.

LAUER: And it's funny because President Bush looked at it from the other way, he worried that a Republican president coming into a state with a Democratic governor and a largely African-American population and declaring martial law basically would be viewed very badly.

NAGIN: Yeah, but Americans were suffering and I thought that at that particular point in time the President, in my opinion, should have stepped in, categorized this as a catastrophe and did what he had to do to bring troops in.

LAUER: In a radio interview you did, I think it was three days after the storm hit, you started to talk about the response. I just want to play you that clip of that radio interview.

NAGIN: Don't tell me 40,000 people are coming here. They're not here. It's too doggone late. Now get off your asses [bleeped out] and let's do something and let's fix the biggest goddamn [bleeped out] crisis in the history of this country.

LAUER: You had reached a tipping point. What was it that put you over the edge?

NAGIN: Well, I was sitting in New Orleans and I was watching the people suffering. I kept getting promises and nothing was going to happen. And then I was listening to these radio interviews where they were saying that everything was okay in New Orleans. You were covering it. Your network was covering it. People knew that it was different. So I just had had enough. And my temper took over.

LAUER: And even as I sit across from you, Ray, and at the time as mayor you had your critics.

NAGIN: Oh, yes.

LAUER: And there were people who said that, 'He was part of the problem, not the solution.' So I know you admit in the book that you made mistakes.

NAGIN: Absolutely.

LAUER: What was the biggest mistake you made?

NAGIN: Well, you know, it was a catastrophic event. We all made mistakes at every level of government. But I think the thing that I worry about and I think about the most is could I have called a mandatory evacuation much earlier. It was the first one in the almost 300-history of the City of New Orleans. I had about an eight to ten-hour window overnight where I could have called it.

LAUER: You think you could have changed the scope of the suffering?

NAGIN: I'm not sure. It was overnight, so most people were preparing to leave that next morning anyway. But it was a window that I think about a lot.

LAUER: Former New Orleans Mayor Ray Nagin. Ray, it's always good to see you. Thank you very much.

NAGIN: Self-published on CreateSpace, Amazon.

LAUER: And the book is called 'Katrina's Secrets.' Ray, thank you very much.

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